Electric switch



G. J. MEUER 2,658,978

ELECTRIC SWITCH Nov. 10, 1953 Original Filed Oct. 29, 1948 2 Sheets-Sheet l 47C 64 I7 59 47545 47d Nov. l0, 1953 G. J. MEUER 2,658,978

ELECTRIC SWITCH Original Filed Oct. 29, 1948 2 Shee's-Sheefl 2 Patented Nov. 10, 1953 ELECTRIC SWITCH George J. Meuer, Milwaukee, Wis., assignor to Cutler-Hammer, Inc., Milwaukee, Wis., a cor--` poration of Delaware Original application October 29, 1948, Serial No.

Divided and this application March 15, 1951, Serial No. 215,808

7 Claims. (Cl. 20G-168) This invention relates to electric. switches and more particularly to improvements in switch bases and wiring terminals. carried thereby.

This application is a division of my application Serial No. 57,378, filed October 29, 1948, now Patent` No. 2,571,467', issued October 16., 1951.

A primaryv object ofthe present invention is to provide an improved form of switch base, and

Another object is to provide a switch base with improved construction and arrangement of its wiring terminals.

Otherfrobjects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate a preferrea embodiment of the invention which will now be described, it being understood that the embodiments' illustrated are susceptible of modification in respect todetails. without departing from the scope of the appended claims.

Inthe drawings Figure i is an elevational view of a switch (twice normal scale),- showing the. bottom side oi a, molded insulating base-the contactwiring ter-v mirials and an auxiliaryA wiring lug being shown in position;

liig.d 2; is a sectional view, on the line 2--2 of Fg.-. 1.?,

Eis. 3 is a Sectional view, on theI line 3-3 of Fig. l showing the switch contacts andV wiring terminals;-

Fig. 3A is a fragmentary view of the lower right hand corner portion cf the bottom side of the switch base but with the terminal member, wiring lug and securing rivets removed;

Eig. 4 is a view of the upper surface of the switchbase shown in Eig. l with the operating superstructure cut away;-

Fig. 5` is a sectionalv View, on the line 5-.5 of Fig'. 2, andl Eig; 6 is al fragmentary sectional view of one corner of the switch` base to further illustrate the wiring terminalA associated with. certain of the switch contacts.

Referring to the drawings, generally considered they show a switch comprising a switch base in which are'carried stationary and movable contacts and anv operating superstructure of the trigger type. Thev arrangement of the stationary andy movable contacts in the switch base is similar to` that disclosed in'4 the Krieger Patent 2,295,668, issued September l5, 1.942-, although differing therefrom in respect of certain details. A s will now be described the switch base ofthe instant form of switch differsfrom that disclosed in the Krieger patent; in respect of. its

wiring terminals and close the upper surface of the switch base.

More particularly considered the numeral I5 designates a preferred form of molded insulat-A ing base formed of any suitable insulating mate-f rial such as melamine resin. Opening to the upper surface I5a of base I5 are three longitudinally parallel recesses I6, Il, tas best shown in Fig. 4. The opposite side recesses I Ii and I8 are suitably formed, as. best shown in Fig. 3., to accommodate respectively pairs of stationary contactv members i9, I9 and cooperating spring biased vsubstantially U-shaped bridging contactors 2li, Zllv which underlie respective pairs of the contact members i9, I9. On Atheir bottom surfaces contact. members I9 are provided with contact tips Ita which are preferably formed of silver or a silver base material and which are suitably secured to members I9 as by spot welding. Mov,- able contactors 20, 20 are provided on the upper surfaces oftheir outwardly extending arms with contact tips 29a which are adapted to engage with the stationary contact tips |93. Each. of' the movable contactors 20 has bearing against its. in

termediate portion one end of a coil compression spring 2.I which spring bears at its opposite end against the bottom of the respective recess I6 or I8 as best shown in Fig. 3. The contact members I9 are secured within recesses I6 and I8 by rivets 22 which extend through suitable openings formed in base |15 to the bottom side of said base.

A fiat punched insulating plate 23 is accomrnoE dated edgewise and transversely of recesses lI', l-'I and i8. in alined notches 24 and 25 which respec.-

tively interconnect recesses I6..-IT and recesses Ile-I8; Also end portions of plate 23 are accom* modated within the U-shaped intermediate por tions of contaotors 20 to bear upon said contac.-

tors as bestl shown inFigs. 3 and 4.

Overlying the upper edge of plate 23 and located in base recess Il is a cam operating member 26. Cam 26 comprises a strip having a flat portion 26a which overlies the upper edge of plate 23' and which at one end is of T-shape, as best shown in Fig. 4. The T-shape end of portion 28a is located within a corresponding T-shapeI portion I7'r1 of recess Il opening to the upper surface I5a ofA base I5. The bottom wall of recess Hf* slopes upwardly from a shoulder of recess I'I at a slight angle toward the upper surface I5 of the base, as best shown in Fig. 2. The cam 26 has a portion 2Gb which projects upwardly from the free end of portion 26a at a right angle there-v from and which extendsl through a small rectangular opening 'formed in a flexible rubber or rub the means utilizedk to enber-like diaphragm 21 of sheet form that overlies the upper surface I5a of the base. Further the cam 26 has at the upper end of portion 26h and exposed above the diaphragm 21 a portion 26c which bears substantially at a right angle to portion 26b and which is in a substantially parallel and overlying relation to the portion 26a. Additionally cam 26 has a portion 26d extending from the portion 26c at an obtuse angle toward the portion 26a, said portion 26d having a free end. Adjacent its free end the portion 26d is concavely curved in its longitudinal dimension.

Diaphragm 21 overlying the upper surface I5a of the base affords a substantially dust-tight enclosure for recesses I6, I1, I8 and I1a and for the notches 2d and 25. It also affords retention of the T-shape end of cam 26 within recess I'Ia wherein said cam is afforded pivotal bearing support.

As will be apparent, when cam 26 is pivotally z.

moved inwardly of base I5 it causes plate 23 to move downwardly in said base against the bias of springs 2l, 2I bearing upon contactors 2B, 26, thereby effecting disengagement of the contact tips a of the contactors from contact tips I9a of the stationary contact members I3 for circuit interruption. When the cam 26 is relieved of down- Ward pressure the springs 2I act on the contactors to reengage them with the stationary contact members and to return said cam to its outer extreme position.

Whereas in the aforementioned Krieger patent a molded insulating cam member is utilized, I nd that the cam 26, formed as by the stamping and punching of a strip of sheet metal, is particularly useful in conjunction with the diaphragm 21.

Base I5 on its outer face paralleling the aforedescribed recessed face is provided with a longitudinally extending, substantially rectangular central rib I5b as best shown in Figs. 1 and 2. Intersecting the rib I5b at a point midway between its opposite ends and lying on opposite sides thereof are ribs I5, I5, whose form is best shown in Figs. 1, 3 and 5. The ribs I5b and I5c separate, and act as barriers between, the four corner portions 28, 29, and 3I of the surface of the base from which said ribs project.

The base surface portions 28, 29, 30 and 3l are alike in form. By Way of example, as best shown in Figs. 1, 3 and 6, the portion 28 has surfaces 28a and 28 lying in different parallel planes and a sloping interconnecting surface 28b which as shown does not meet the surface 28c exactly but is slightly offset therefrom, the intermediate surface being perpendicular to surface 28C. As best shown in Figs. 3 and 3A, surface 28b has formed therein an opening which gives access to a recess 28e in the base, said recess having parallel side walls and intermediate Walls meeting to give the recess a triangular form. Also, as best shown in Figs. 3, 3A and 6, the surface 28c has a small rectangular opening therein giving access to a recess 28r extending inwardly of said base for a short distance, the recess to receive with a snug llt a rectangular part. Each of the other recesses 29, 36 and 3i have surfaces and recesses like those aforedescribed in connection with portion 28 and in each instance such surfaces and recesses are designated by identical subscripts.

As best shown in Figs. l, 3 and 6, like terminal members 32 are mounted on portions 28, 29, 33 and 3| of the base. Each terminal member 32 is provided with a reduced rectangular end extension 32a to project into one of recesses 281, 23f,

30f, 3If, such extension being an integral part of a portion 32b carrying a binding screw 39, the shank of which extends into one of the recesses 28e, 29e, 362, 31e. Portions 32c of said terminal members 32 are perforated to accommodate the Shanks of the rivets 22 which in addition to their function aforedescribed afford rigid securement of members 32 to base I5 and electrical connection of each terminal member with a stationary contact member I3.

As will be noted, the arrangement of terminal members 32 is substantially different from that disclosed in the aforementioned Krieger patent. The instant arrangement facilitates the making of Wire circuit connections with the switch and prevents disturbing the alinement and positioning of the stationary contact members I9 within the switch base. Any strains occurring in the making of wire connections are localized to the terminal members 32. It will also be noted by those skilled in the art that the arrangement of terminal members 32 provides access for making the equivalent of bottom and/ or end wiring connections therewith.

An auxiliary wiring lug 33 is secured to the base I5 centrally with respect to the four terminal members 32 as best shown in Figs. 1, 2 and 5. Lug 33, which is preferably formed by stamping and punching of a strip of brass, is provided With a flat, elongated oval shape portion 33B which engages with the rib I5a of base I5 between the ribs |50, I5 thereof. Lug 33 is also provided with small rectangular extensions 33h, 33b which project at a right angle to the portion 33a on opposite edges of the latter. A circular opening is provided in the portion 33a midway between its ends to accommodate a short cylindrical boss I5f of base i5 which extends outwardly between the ribs I5, 15.

Two other circular openings of smaller diameter are formed in the portion 33a on opposite sides of the aforementioned opening. A hollow rivet 34 penetrates lug 33 through one of the last mentioned openings, said rivet being contained in a recess I5g of base I5 and extending outwardly from said base. Recess I5g in the instant form of switch is broached through to communicate with the recess i1, the bottom wall of which is of slightly greater width than that of recess 15g. Rivet 34 is provided with a rectangularly shaped head snugly fitting recess IIa and with a shank extending through recess I5g and lug 33 to have its end upset over the outer surface of lug 33 to thereby secure the latter to base I5. Rivet 34 is suitably threaded internally to receive a binding screw 35. The other of said openings in lug 33 is suitably threaded to receive a binding screw 36 which extends inwardly of base I5 within a clearance recess I5h formed in the latter. A thin fiber insulating member 31 having a shape like that of the portion 33a of lug 33, but at all points extending a substantial distance therebeyond, is interposed between lug 33 and base I5.

As will be understood, the lug 33 and the parts associated therewith have no electrical connection with the terminal members 32 or stationary contact members I3 and is provided as an auxiliary bussing lug or wiring bracket for convenience in anchoring wires to the switch.

A combined cover and frame member 38, preferably formed by punching and stamp-ing a sheet metal plate has a portion 38B which in part overlies the surface I5EL of base I5 and portions 381 and 36c which extend beyond said base. As

viewed in Eig. 5,.the. portion 3,3 ot said memben is. otsubstantially. ix1'm ited.E channel: shape in verftical. cross section.- `v Asfbest shown. in. Fig .2r the; port-lori a. pair'- of" openings. 392 and; M.' eX-. tending therethrough.' and formed." for counter- 1 sinking! of the. upset ends' of rivets 4 Ii: which. puto,-` vide. for securementfof member 3.8 base.y |551' @penings 3%)y 4th register. respectively with. openings. li 2=y and1 4.3. extending; through: base L5; andi being.- enlarged` adjacent' the surface. ot the base to provide inset annular; shoulders ror-abut' ment by.' the heads. of the rivets 4I A stiff liber. insulating; `plate '44' coextensi've. with, the. surface 1:5@of base. I5.l andi diaphragm 2.1.- andhaving a. rectangularcentral opening '44ais positioned betweenithe portion 318e of. member. 3B. and. a Horrible-fiber member..` 45.; overlyingI dia;Y phfragm 2.1; Members'. 44:*y and 415 `'have openingsVV to accommodate the: Shanks-ofrivets. 41.'.

Although. not shown in the drawings, thememberl 45am practice would. commonly extend beyond the` outer sidewalls of.' base l'5 as viewedin llig. 1

to.be.bent toiorm ari. insulating envelope around the bottom. of base. |15 to protect against grounding of. Wires connected` to theterminal members 32 and the lug 3'3.

Asbest shown in. Figs. l. and 2.-, the member 38. at the end of1 portion, 318% turns inwardly. provid.- ing a` portion 38b parallelingthe end of base. l5; andv at the endl ofy portion 38.1? turns. to provide a portion 38.0- ly'ing-in a plane paralleling. that of por-tion, 38o. Extending from the portion 389'is a halt-moon. shaped lugvilfd which depends atan.r angleto the. pianeuofportion` 3.89; IThe portion- 38.cr merges with` a portion. 3 8# whichisr slightly. off-1 set therefrom andalsowith.V a portion 3stA which is onset; therefrom to a; greater degree. A lug 385s slieared from the portion 3,8?.projectsl-r-at a; rig-ht angle. thereto and provides. support for-a coiled` a slot 47hv freeing it or. reciprocationv Without interference bythe penetrating connection comiprisiii-g right hand; rivet'4l. Portion 418L hasat'its free end a rectangular extension 4'1i toV bear upon` and to.. oo more@ oloo'etho. portions. 26 one' 416"- ofloomz.. Said extention boing' outwardly. tornooi' and. voroiootite toto o. Channel. rroridod: in.; 'part 3.8a of` member 3,8'. Portion'. 4,1gt of member 4'l'is Connected with a portioryl 4.1"* Whotibooro. oto. right angle thereto and which lies.l in a parallel relation With. the portion. 38P- oi member- 38. Portion 41do toro. isoonnooted rito a, portion. kleiv which boots at; arishtonsle; thorofaromfin o. parallel. relation. to the portion. 41a;v and which along a greater'portion otitslength is of reduced width. Adjacent'its. free. end the-portion 4.16, isprov'dedf with a circular opening Vtlfirougli which extends a reducedr portion of a tubular; bushing. 48. BushingV 48 is` rigidly` secured: to. portion' 4.1% by. upsetting` of the end. of said reduced`V portion ofsaid bushing which. extends beyond said portion 41e;

For. actuation. of member 41fthereis provided a trigger typeactuator 49 which. is. similar informA to certain trigger actuators disclosed in Patents 1,889,259.; 1,9.7'75078-and 2,0895032, However, as will noW- be described, theinstanttrigger actuator differs in respect of-` certain details oi: construction, its, operating connections the.

l'nOi aimed openingsl formed inthe side portions andliSP -ofsaid actuator and through a hollow.y bushing 5t penetrating the, portion: :i8e and being: secured thereto.. in the manner.'aforeindicatedior thejbllShiIlgAg; Pin. 501. is provid-ed at` one end withl an enlarged head` which` bears; against the..

outer-surfe@ of; portion 49e and at its opposite. end is,l upsetl over: the outer-surface. of' the pore. tion 749k," thereby being secured against axialv movement. The portion 497C.- is -depressedyat a point between the portions 493.. and '4.911130 form an.'v

abutment tor Spring 4t,- Portions 49o ond 4%.- are provided with addi-tional alined openings foro cyliodriooipin 5;'2 Whiotxoxtoodo. through tho busti-ee f4.8y and which. is Soourod to tho actuatorin the manner aforeindicated for the pin 50. The

S11-eels diamototofein. 5251s substorltiollyv'ls A than the.: inner `diameter of bushing 48.

AsJ will-be ondersteod,` spring l biases actuator 4,9 for pivotalrnovernent the clockwise direction asvv-iewed in Fig. 1=, but such movement being limited to engagement. of the shonltotoiro 552; with the] marginal. Sido ot portion i8?` ofv mom:

ber AsY shown in Fig. 1, two: circular openingsia.

andy54 are provided portion 38 of memberi... to. prov-ide for attahment ofthe switch: assertief blt-within.- o tool handit or other 11o-.usine oo or bolts or torero. W-hioh oro oooommodatedby. said-A l theswitoh stands in Figs. 1 and A2, the inem ber 471V- is. moved to `its extreme. left position due t0.v the bias 'of springv 46 which acts thereon terrors@ ootootory 4 8, om, 51. on@ bushing. 4,8.H AS.A

@erodoto-rito@ member 4111s in oooh oostuoa, its portion. 41o. engages with the portion, "ist` ofcam 2,6,` andv thereby eiieotsi disengagement, of the. conta.etersI 2i). from the` stationarycontact members; *it As W111i. bo. oporooiated., m its extolotioo shown in Fia, 1, spring; 46. must be strongrenough to over-power. the springs 2 1, 21 in svllitoh.A base to collapse the same.

Whoo tto ootuotot 49 'is oivotolly moved trattato bias of spring to. in too countorolook.-

ditto oa. viowoo Fie- 1. the om 521soerooo' @ist intake-11o the olor thereof` Within tto busti-oo; eed. tooo to -eoeose-theopposite Wall 0f. 4o and, more member' 4J: to the right ombot 4l is moved Sufoontly far-to the `right its portion 4J. .move out of engossoooet eta tho. portion Ztcoi Corn 26. and onto .portion zo@ of the latter.V 'jhen the bias.- oi Sorteos 24:. looting through colf-.liaotors2.0,A 205 member-2 e and cam. Z6. causes. member 4J; yto move, to; the. right with more'or less snap action. As a resultfthe. contactors 2:05 2b engage with the stationary contact members. I9 andthebushing 4fmoves tree. ory the shank of: pin 52"until it again reeengag-.esf with the same on the opposite side. The. subsequent refengagement of bushing '48- with pin 52.' `provides audible signal and a tactile perceptible signal: vwhich is transrnittelztv through .pin 52. and 'actuator-."4il to. indicateV that' the switch has been operated to its circuit completing condition. Actuator 9 may only be moved against the bias of spring 46 to a limited extent and is moved to such limit when the bottom surface of its portion 49 engages with the lug 38d of member 38. Releasing the actuator 49 for movement under the bias of spring 46 effects return of the switch to its circuit interrupting condition aforedescribed.

Iclaim:

1.v As an article of manufacture, a punched and stamped sheet metal wiring terminal member having a perforated fiat portion at one end thereof, a second flat portion extending in a given direction from said iirst portion at an obtuse angle thereto, said second portion having a tapped opening formed therein to accommodate the shank of a binding screw, and a third portion of reduced width extending in a. generally similar direction from said second portion in a plane substantially perpendicular to the plane of said first portion, said first portion being adapted for rigid attachment to an insulating base through the medium of a suitable fastening member, and said third portion being adapted to t rather closely within a suitable recess in the base to anchor that end of said terminal member.

2. In an electric switch, in combination, a. plurality of punched and stamped sheet metal wiring terminal members each of which comprises a flat portion at one end thereof and a portion of reduced width at the other end thereof extending at an angular relation to said portion rst mentioned, said members each having a tapped opening formed therein, a corresponding number of binding screws the Shanks of which are engaged with the threads in the respective openings, a molded insulating base of substantially rectangular contour having a recess opening to the upper surface thereof, the lower surface of said base having upwardly offset recesses formed therein at the respective corners thereof whereby integral insulating barriers of substantial height are provided therebetween, said last mentioned recesses each having wall surfaces so shaped as to provide for seating of said flat portions of said terminal members thereagainst and each of the latter recesses having an auxiliary recess opening thereto to respectively accommodate the shanks of said binding screws and an auxiliary recess opening thereto to respectively accommodate said reduced portions of said terminal members to provide for anchoring of said reduced portions, said base having a plurality of openings extending therethrough, and a corresponding number of fastening members penetrating said openings in said base and said flat portions of the respective terminal members to provide for rigid attachment of the latter to said base. Y

3. In an electric switch, in combination, a plurality of punched and stamped sheet metal wiring terminal members each of which comprises a perforated fiat portion at one end thereof, an intermediate portion extending from said flat portion at an obtuse angle thereto and having a tapped opening formed therein, and a portion of reduced width extending from said intermediate portion in a substantially perpendicular relation to said flat portion, a corresponding number of binding screws the shanks of which are engaged with the threads of the respective openings, a molded insulating base of substantially rectangular contour having a recess opening to the upper surface thereof, the lower surface of 8 said base having upwardly offset recesses formed therein at the respective corners thereof whereby integral Yinsulating barriers of substantial height are provided therebetween, said last mentioned recesses each having wall surfaces so shaped as to provide for seating of said flat and intermediate portions of said terminal members thereagainst and each of the latter recesses having an auxiliary recess opening thereto to accommodate the shanks of said binding screws and an auxiliary recess opening thereto to accommodate said reduced portions of said terminal members to provide for anchoring said reduced portions, said base having a plurality of openings extending therethrough, and a corresponding number of fastening members penetrating said openings in said base and said flat portions of said terminal members to provide for rigid attachment of the latter to said base.

4. In an electric switch, in combiation, a

molded insulting base of substantially rectangu` lar contour having a recess opening to the upper surface thereof only, the lower surface of said base having upwardly odset portions forming recesses at each of the four corners thereof with integral insulating barriers therebetween, a plurality of like punched and stamped sheet metal wiring terminal members each adapted to seat within one of said corner recesses, each of said members consisting of a perforated flat portion at one end thereof, an intermediate fiat portion extending upwardly from said first mentioned portion at an obtuse angle thereto and having a. tapped opening formed therein, and an end portion of reduced width extending upwardly' from said intermediate portion in a plane substantially perpendicular to the plane of said nrst'mentioned portion, a corresponding number of binding screws the shanks of which are adjustable within the respective tapped openings,

each of said corner recesses being shaped to afford clearance for the respective screw shanks and to accommodate with a fairly close fit the reduced end of the terminal member associated therewith, whereby said reduced end is anchored, a corresponding number of perforated stationary contact members positioned within said rst mentioned recess, said insulating base having passages extending therethrough and alined with the perforations in the respective contact and terminal members, and a corresponding number of fastening members penetrating said perforations and passages to provide for securement of all of said parts in assembled relation and electrical connection of each contact with its associated terminal member.

5. In an electric switch, in combination, a molded insulating base having a recess opening to the upper surface thereof and a longitudinal rib extending from the lower surface thereof, said rib having opening to its outer surface a pair of recesses, one of said rib recesses communicating with said iirst mentioned recess, a punched and stamped sheet metal wiring terminal having a pair of openings formed therein, one of said openings being alined with said one of said rib recesses while the other of said openings is tapped and alined with the other of said rib recesses, a hollow tapped fastening member penetrating said one of said rib recesses and said one of said openings in said terminal, said fastening member having a head at one end thereof seated against said base within said rst mentioned recess, said fastening member at its opposite end being upset over said terminal member to provide for rigid attachment of the latter to said base, and a pair of binding screws the Shanks of which respectively engage with the tapped openings in said fastening member and said terminal to provide for anchoring of conductors to the latter.

6. In an electric switch, in combination, a molded insulating base having a recess opening to the upper surface thereof and a longitudinal rib extending from the lower surface thereof, said rib having formed integrally therewith intermediate its ends a cylindrical boss, said rib having opening to its outer surface a p-air of recesses which are located respectively on opposite sides of said boss, one of said rib recesses communicating with said first mentioned recess, a punched and stamped sheet metal auxiliary terminal member having a central opening to accommodate said boss and openings on opposite sides of said central opening, one of the latter openings being alined with said one of said rib recesses and the other opening being tapped and alined with the other of said rib recesses, an insulating plate having perforations alined with the respective openings in said terminal member, said plate being interposed between said terminal member and said rib, a hollow tapped fastening member penetrating said one of said rib recesses and said terminal, said fastening member having a head at one end thereof which seats against said base within said rst mentioned recess, said fastening member at its opposite end being upset over said terminal member to provide for rigid attachment of the latter and said plate to said base, and a pair of binding screws the shanks of which respectively engage with the tapped openings in said fastening member and said terminal member to provide for anchoring of conductors to the latter.

7. In an electric switch, in combination, a molded insulating base having a recess opening to the upper surface thereof, the lower surface l0 cylindrical boss, and said longitudinal rib having opening to its outer surface a pair of recesses which are located respectively on opposite sides of said boss, one of said ribrecesses communicating with said first mentioned recess, a plurality of like wiring terminal members each of which is seated within one of said corner recesses, a corresponding number of fastening members securing said terminal members to said base, a punched and stamped sheet metal auxiliary wiring terminal member having a central opening to accommodate said boss and openings on opposite sides of said central opening, one of the latter openings being alined with said one of said rib recesses and the other opening being tapped and alined with the other of said rib recesses, an insulating plate interposed between said auxiliary terminal member and said longitudnal rib of said base, said plate having perforations alined with said openings in said auX- iliary terminal member, said plate extending at all points beyond the marginal edges of said auxiliary terminal member to provide an arc barrier between the latter and said terminal members first mentioned, a hollow tapped fastening member penetrating said one of said rib recesses and said auxiliary terminal member, said last mentioned fastening member having a head at one end thereof seated against said base within said first mentioned recess, said last mentioned fastening member being upset atits opposite end over said auxiliary terminal member to provide for rigid attachment of the latter and said plate to said base, and a pair of binding screws the shanks of which respectively engage with the tapped openings in said last mentioned fastening member and said auxiliary termina1 member to provide for anchoring of conductors to the latter.

GEORGE J. MEUER.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,449,460 Thomas Mar. 27, 1923 2,106,581 Unwin Jan. 25, 1938 2,488,670 Koenig Nov. 22, 1949 2,539,628 Kingdom Jan. 30, 1951 

